The secure key rate is calculated as \(R=3.45\times 10^{-8}\) , which is about 3.45 bps considering our system frequency. We plot this value and the theoretical simulation in Fig. REF , where we also plot recent TF-QKD experimental results as a comparison. With the improvement in both theory and experiment, our secure key rate is more than 10 times higher than the absolute PLOB bound. The secure key rate is also 3 orders higher than previous field test MDI-QKD experiment [1]}, if considering linear decreasing and assuming no detector dark count. This result demonstrates the capability of the SNS-TF-QKD protocol with AOPP in practical environment with field deployed fibers.
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